The use of non-steroidal antiinflammatory drugs (NSAIDs) in treating pain and the swelling associated with inflammation also produce severe side effects, including life threatening ulcers. The recent discovery of an inducible enzyme associated with inflammation (“prostaglandin G/H synthase II” or “cyclooxygenase-2 (COX-2)”) provides a viable target of inhibition which more effectively reduces inflammation and produces fewer and less drastic side effects.
Compounds which selectively inhibit cyclooxygenase-2 have been described. U.S. Pat. No. 5,380,738 describes oxazoles which selectively inhibit cyclooxygenase-2. U.S. Pat. No. 5,344,991 describes cyclopentenes which selectively inhibit cyclooxygenase-2. U.S. Pat. No. 5,393,790 describes spiro compounds which selectively inhibit cyclooxygenase-2. WO94/15932 describes thiophene and furan derivatives which selectively inhibit cyclooxygenase-2. WO94/27980 describes oxazoles which selectively inhibit cyclooxygenase-2. WO94/13635 describes compounds which selectively inhibit cyclooxygenase-2. WO94/20480 describes compounds which selectively inhibit cyclooxygenase-2. WO95/15316 describes pyrazolyl sulfonamide derivatives which selectively inhibit cyclooxygenase-2. However, in some circumstances, prodrugs of antiinflammatory compounds are advantageous, especially where the prodrugs have increased water solubility or delayed onset of action.
Substituted sulfonamides have been described. Pyrazolyl-sulfonylureas have been described as having possible hypoglycemic activity [H. Faid-Allah and H. Mokhtar, Ind. J. Chem, 27, 245 (1988)]. JP 1,045,374 describes water soluble tetrazolium compounds useful in assays for determining reducing substances. D. Mukerjee et al [Acta. Pharma. Jugosl., 31, 151 (1981)] describe tetrazolium sulfonamides as antiviral agents. JP 4,277,724 describes triphenyl pyrazolines as nonlinear optical material. JP 5,323,522 describes the use of heterocyclic compounds in black and white photographic material. U.S. Pat. No. 5,389,635 describes substituted imidazoles as angiotensin II antagonists. U.S. Pat. No. 5,387,592 describes substituted benzimidazole derivatives as angiotensin II antagonists. G. Dorofeenko et al [Khim. Farm. Zh., 16, 920 (1982)] describe pyridinium salts as antiviral agents. U.S. Pat. No. 5,338,749 describes diaryl-substituted heterocyclyl compounds as antiarthritis agents. WO94/26731 describes thiophene compounds which selectively inhibit cyclooxygenase-2. WO95/00501 describes compounds which selectively inhibit cyclooxygenase-2, and specifically, 3-(4-(trifluoroacetylaminosulfonyl)phenyl)-2-(4-fluorophenyl)thiophene is described. T. Ivanov [Mh. Chem., 97, 1499 (1966)] describes the preparation of diarylindone derivatives as possible indicators, and 2-(4-(N-methylaminosulfonyl)phenyl)-3-phenylindone is specifically described.
J. Larsen and H. Bundgaard [Int. J. Pharmaceutics, 37, 87 (1987)] describe the evaluation of N-acylsulfonamides as potential prodrug derivatives. J. Larsen et al [Int. J. Pharmaceutics, 47, 103 (1988)] describe the evaluation of N-methylsulfonamides as potential prodrug derivatives.
There currently exists a need for compounds suitable for injectable antiinflammatory compositions. The compounds of the present invention are found to show usefulness as prodrugs.